decades of development, carbonylation reactions have become one of the most powerful tools in modern organic synthesis. However, the requirement of CO gas limits the applications of such reactions. Reported herein is a versatile and practical protocol for carbonylativereactions which rely on the cooperation of phenyl formate and nonaflate, and the generation of CO in situ. This protocol has a high functional‐group
Sunlight-Driven Decarboxylative Alkynylation of α-Keto Acids with Bromoacetylenes by Hypervalent Iodine Reagent Catalysis: A Facile Approach to Ynones
作者:Hui Tan、Hongji Li、Wangqin Ji、Lei Wang
DOI:10.1002/anie.201503479
日期:2015.7.13
A novel and practical decarboxylativealkynylation of α‐keto acids with bromoacetylenes is catalyzed by hypervalent iodine(III) reagents when irradiation by sunlight at room temperature. The product ynones are generated in good yields. Experiments show that results obtained with blue light (λ=450–455 nm) are comparable to those obtained when using sunlight. Mechanistic studies demonstrate that the
A novel and efficient approach for the synthesis of functionalized isoxazoles viapalladium-catalyzed cascade annulation/allylation of alkynyl oxime ethers with allyl halides has been established. The present protocol exhibits mild reaction conditions, good functional group compatibility, and convenient operation. Moreover, scalability was performed and further decoration of the isoxazole product was
[4 + 1] Cycloaddition Reaction of α,β-Alkynic Hydrazones and KSCN under Transition-Metal-Free Conditions: Synthesis of <i>N</i>-Iminoisothiazolium Ylides
作者:Bei-Bei Liu、Wen-Bin Cao、Fei Wang、Shun-Yi Wang、Shun-Jun Ji
DOI:10.1021/acs.joc.8b01725
日期:2018.9.21
A novel heteroannulation reaction between α,β-alkynic hydrazones and potassium thiocyanate has been developed for the synthesis of N-iminoisothiazolium ylides. The transformation features wide substrate scope, functional tolerance, and easy operation. This investigation involves a [4 + 1]-type cycloaddition reaction and C–S/S–N bond formation under transition-metal-free conditions. The application
A silver-mediated cascade trifluoromethylthiolation and cyclization has been developed for the synthesis of 2-(trifluoromethylthio)-indenones. A variety of arylpropynones underwent this radical oxidative cyclization with AgSCF3 to afford trifluoromethylthiolated indenones in moderate to excellent yields.